Setting Travel Limits And Cutoffs; Setting Alerts - Emerson Fisher FIELDVUE DVC2000 Instruction Manual

seconds deactivates this feature and allows the valve
to stroke closed as fast as possible.
D Integral Gain—By setting this value to 0.0 the
positioner integrator is disabled. Any other value will
provide reset action to improve static performance.
D Integral Dead Zone—When the travel target and
actual target deviate by less than this amount, the
integrator is automatically disabled. This prevents the
positioner integrator from fighting with the process
controller integrator which may result in valve
oscillation.

Setting Travel Limits and Cutoffs

Select Setup & Diag, Detailed Setup, Response
Control, and Limits & Cutoffs. Follow the prompts on
the Field Communicator display to set the Tvl Limit
High (Travel Limit High), Tvl Limit Low (Travel Limit
Low), Tvl Cutoff High (Travel Cutoff High), and Tvl
Cutoff Low (Travel Cutoff Low).
D Tvl Limit High—Travel Limit High defines the high
limit for the travel in percent (%) of ranged travel. It is
the maximum allowable travel (in percent of ranged
travel) for the valve. During operation, the travel target
will not exceed this limit. When a Travel Limit High is
set, the Travel Cutoff High is deactivated, since only
one of these parameters can be active. Travel Limit
High is deactivated by setting it to 125.0%.
D Tvl Limit Low—Travel Limit Low defines the low
limit for the travel in percent (%) of ranged travel. It is
the minimum allowable travel (in percent of ranged
travel) for the valve. During operation, the travel target
will not exceed this limit. When a Travel Limit Low is
set, the Travel Cutoff Low is deactivated, since only
one of these parameters can be active. Travel Limit
Low is deactivated by setting it to −25.0%.
D Tvl Cutoff High—Travel Cutoff High defines the
high cutoff point for the travel in percent (%) of ranged
travel. Above this cutoff, the travel target is set to
123.0% of the ranged travel. When a Travel Cutoff
High is set, the Travel Limit High is deactivated, since
only one of these parameters can be active. Travel
Cutoff High is deactivated by setting it to 125.0%.
D Tvl Cutoff Low—Travel Cutoff Low defines the
low cutoff point for the travel. Travel Cutoff Low can
be used to ensure proper seat load is applied to the
valve. When below the travel cutoff low, the output is
set to zero or to full supply pressure, depending upon
the zero control signal. A Travel Cutoff Low of 0.5% is
recommended to help ensure maximum shutoff seat
loading.
July 2009
Detailed Setup and Calibration
When a Travel Cutoff Low is set, the Travel Limit Low
is deactivated, since only one of these parameters can
be active. Travel Cutoff Low is deactivated by setting it
to −25.0%.

Setting Alerts

The following menus are available for configuring
Alerts. Items on the menus may be changed with the
instrument In Service. Protection does not need to be
removed (no need to set to None). Alerts are not
processed when a Diagnostic is in progress.
Alerts are not available with
instrument level AC.
Setting Travel Alerts
Setting High, High-High, Low and
Low-Low Alerts
Select Setup & Diag, Detailed Setup, Alerts, and
Travel Alerts. Follow the prompts on the Field
Communicator display to set: Tvl Hi/Lo Enab (Travel
High and Low Alert Enable), Tvl HH/LL Enab (Travel
High High and Low Low Alert Enable), Tvl Alert Hi Pt
(Travel Alert High Point), Tvl Alert Lo Pt (Travel Alert
Low Point), Tvl Alert Hi Hi Pt (Travel Alert High High
Point), Tvl Alert Lo Lo Pt (Travel Alert Low Low Point),
and Tvl Alrt DB (Travel Alert Deadband).
D Tvl Hi/Lo Enab—Yes or No. Travel Hi/Lo Enable
activates checking of the ranged travel against the
Travel Alert High and Low Points. Travel Alert Hi is set
if the ranged travel rises above the alert high point.
Once the alert is set, the ranged travel must fall below
the alert high point by the Travel Alert Deadband
before the alert is cleared. See figure 4-3.
Travel Alert Lo is set if the ranged travel falls below
the alert low point. Once the alert is set, the ranged
travel must rise above the alert low point by the Travel
Alert Deadband before the alert is cleared. See figure
4-3.
D Tvl HH/LL Enab—Yes or No. Travel HH/LL
Enable activates checking of the ranged travel against
the Travel Alert High-High and Low-Low Points. Travel
Alert Hi Hi is set if the ranged travel rises above the
alert high-high point. Once the alert is set, the ranged
Note
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